+
−"""
+
− This object provides quoting for GEOS geometries into PostgreSQL/PostGIS.
+
−"""
+
−
+
−from django.contrib.gis.db.backend.postgis.query import GEOM_FROM_WKB
+
−from psycopg2 import Binary
+
−from psycopg2.extensions import ISQLQuote
+
−
+
−class PostGISAdaptor(object):
+
−    def __init__(self, geom):
+
−        "Initializes on the geometry."
+
−        # Getting the WKB (in string form, to allow easy pickling of
+
−        # the adaptor) and the SRID from the geometry.
+
−        self.wkb = str(geom.wkb)
+
−        self.srid = geom.srid
+
−
+
−    def __conform__(self, proto):
+
−        # Does the given protocol conform to what Psycopg2 expects?
+
−        if proto == ISQLQuote:
+
−            return self
+
−        else:
+
−            raise Exception('Error implementing psycopg2 protocol. Is psycopg2 installed?')
+
−
+
−    def __eq__(self, other):
+
−        return (self.wkb == other.wkb) and (self.srid == other.srid)
+
−
+
−    def __str__(self):
+
−        return self.getquoted()
+
−
+
−    def getquoted(self):
+
−        "Returns a properly quoted string for use in PostgreSQL/PostGIS."
+
−        # Want to use WKB, so wrap with psycopg2 Binary() to quote properly.
+
−        return "%s(%s, %s)" % (GEOM_FROM_WKB, Binary(self.wkb), self.srid or -1)